Field of the Invention
The invention relates to an electricity storage battery, such as a redox flow battery.
Description of the Related Art
In the prior art, an electrolyte solution for use in an electricity storage battery is known to contain a metal redox material and a chelating agent (refer to Patent Documents 1 and 2 and Non-Patent Document 1). Patent Document 1 discloses, as an anode electrolyte solution, a specific example containing an iron redox material and ethylenediaminetetraacetatic acid, and a specific example containing an iron redox material and citric acid. Moreover, Patent Document 2 discloses, as an anode electrolyte solution, a specific example containing a titanium redox material and citric acid, a specific example containing a titanium redox material and ethylenediaminetetraacetatic acid, a specific example containing a chromium redox material and ethylenediaminetetraacetatic acid, and a specific example containing a chromium redox material and phosphoric acid. Non-Patent Document 1 discloses, as an anode electrolyte solution, a specific example containing an iron redox material and ethylenediaminetetraacetatic acid, a specific example containing an iron redox material and citric acid, and a specific example containing an iron redox material and oxalic acid.